Just in time for Valentine’s Day – North American flying squirrels, in the genus Glaucomys – glow PINK under UV light! Not fox squirrels, gray squirrels or red squirrels — just the nocturnal flying squirrels. WHY? The authors have several suggestions, including camouflage (other things glow pink at dusk in UV light, such as lichens but also predators such as owls) and even communication. Anyway, it’s a fantastic result – and there is a great summary of it in the Smithsonian, “Flying Squirrels Glow Fluorescent Pink Under Ultraviolet Light” by Meilan Solly.
Kohler, A.M. et al., 2019. Ultraviolet fluorescence discovered in New World flying squirrels (Glaucomys). Journal of Mammalogy, 98, pp.1027–10.